Edward d



(No Model.)

B. D. MAOKINTOSH SWING SAW MACHINE.

Patented Jan. 1 5-, 1889.

Ina/en tar. 44m

Witn asses:

UNITED STATES PATENT FFICEO EDIVARD D. MACKINTOSH, OF BROOKLYN, ASSIGNOR TO PAUL PRYIBIL, OF NEW YORK, N. Y.

swme -sAw MACHINE.

SPECIFICATION forming part of Letters Patent No. 396,217, dated January 15, 1889.

Application filed April 17, 1888.

To all whom, it may concern.-

Be it known that I, EDWARD D. MAOKIN- TOSH, of Brooklyn, in the county of Kings and State of New York, have invented a new and useful Improvement in Swing-Saw Machines, of which the following is a specification.

This invention consists in novel and simple means, hereinafter described and claimed, whereby in the swinging movement of the frame of a swinging saw the saw-shaft and saw may be guided and caused to move in a right line parallel. with the table of the machine.

It also consists in the combination, with the swin gin g-saw frame, of a self-reversing sprin g, applied substantially as hereinafter described and claimed, for the purpose of counterbalancing the weight of the frame and the shafts and their appurtenances.

' In the accompanying drawings, Figure l is a front elevation of a swing-saw machine embodying my invention. Fig. 2 is a side elevation showing the frame in a vertical position, and Fig. 3 is also a side elevation showing the frame in full lines as thrown forward and in dotted lines as thrown back.

Similar letters of reference designate corresponding parts in the several figures.

A designates a swinging-saw frame, provided on its upper end with hollow journals (1, working in the slot-ted guide I) in the bracket B, which is secured to a fixed support, B.

O is the driving-shaft, which, as here shown, is mounted in bearings in the journals a, and which is provided with fast and loose pulleys c c, and also with the pulley 0 from which a belt, 0 drives a pulley, 0, fast on the shaft 0 of the saw or rotary cutter, which has its bearings in the lower part of the frame A. The saw-frame and shaft O swing about the drivin g-shaft C.

At or near the middle of the length of the frame A and on one side thereof is an arm, a, to the end of which is secured, by a pivot, (0 the upper end of a link or bar, D, which is pivoted at its lower end by a pivot, 61, to a support, D, the distance between the centers of its pivots being equal to one-half the distance between the centers of the shafts O and C. The pivot d, which is always fixed while Serial No. 270,925. (No model.)

the saw is in operation, is in line with the line of the rising and falling motion of the axis of the shaft O and in line with the center of'the saw or cutter shaft C when the latter is V61; tically below the shaft 0, as shown in Fig. 2. During the swinging movement of the sawframe the link D, having its pivots at a distance apart equal to half the distance between the centers of the shafts O and 3, causes the shaft 0 to move in a horizontal plane and the shaft 0 to have a vertical movement. The pivot (1 receives the weight of the frame A and the shafts (J 0 and their appurtenances, and in order to provide for the higher or lower adjustment of the said frame and the saw or rotary cutter according to variations in the diameter of the latter or to the height of the work or depth of out, the fixed support D ,in which the said pivot is secured, is made adj ustable, and for this purpose it is represented as consisting of an upright slide, which is fitted to a fixed bracket, 1-3 bolted to the main support or stationary framing ll of the machine. The adjustment of the said slide is repre sented as effected bya screw, D which is con fined lengthwise, but free to turn, in a bearin g, (1, provided on the lower part of said bracket I3 and which works in a female screw-thread in a lug, (1 on the upper part of the slide D. The said screw is turned by a knob or han- 8o dle, d, on its lower end. This adj ustment, when secured, may be retained by a clamping-screw, d", screwing in the support D through a slot, d"', and which may be operated by a handle, (Z As this adjustment takes place without any change of relation to each other of the moving parts of the machine, it does not change the guidiu action of the link; but the swinging movement of the saw or cutter shaft C will always be in a horizon- 9o tal line or parallel with the saw-table whatever may be the height of the saw or cutter relatively to the table, which is of very great importance in some kinds of work.

To guard against lateral strain or movement 5 of the frame A, I provide broad collars a a on one of the journals a, and also provide a lateral guide-bearing, D which is represented as a broad flat surface provided on the upper part of the slide D by a lateral extension 10c thereof, and against which the head of the pivot a bears. For additional security I also provide a fixed straight-faced guide-yoke, d on the movable support D, which embraces the link D and serves as a bearing for the inner face thereof, thereby steadying and directing its movement.

WVhen the frame is swung forward or back of the position shown in Fig. 2, in which the centers of the upper and lower shafts are in the same vertical plane, the center of gravity of the swinging parts falls. To counterbalance to a certain extent the force thus brought into action and tending to move the frame forward orback of a vertical position, a spring, E, secured at one end to the pivot a? and at the other end to a pin, 6, on the slide or support D, is employed, which tends to pull the frame in either direction toward a central vertical line between the two extremes of motion. This pin e is placed nearly opposite the vertical line which the center of the frame would occupy when the frame is vertical, and the spring, turning on the said pin 6, reverses itself, as shown in Fi 3 by dotted lines,which represent it in two positions, so that it pulls in either direction, as required. I prefer, however, not to place the said pin exactly in a central position, but to place it slightly back of said position, so that it is back of the position occupied by the center of gravity of the frame A when the latter is in a vertical posi tion, and that therefore the spring will slightly overbalance the force of gravity when the frame is forward and will under-balance the said force when the frame is back. This arrangement of the pin 6 permits the frame to be carried an d held back by the force of gravitation when not forcibly drawn forward by hand to make a cut.

The frame A is represented as provided with a handle, a whereby the operator may direct the movement of the frame.

It may be noticed that while Ihave referred to the frame A and shaft C as carrying a saw, there maybe substituted for the saw any suitable rotary cuttersuch as can be used in swing sawing machines.

\Vhat I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination, with the swinging and rising and falling frame, the driving-shaft about which said frame swings and which rises and falls therewith, and a shaft for a saw or rotary cutter carried in the lower partof said frame, of a guide-link pivoted at its upper part to the said frame, at about the middle of the length of the latter, and a fixed pivot to which the lower part of said link is connected at a point substantially in line with the line of the rising and falling motion of the frame and opposite the path described by the axis of said shaft in the swinging of the frame, substantially as and for the purpose herein described.

2. The combination, with the rising and falling and swinging frame, the driving-shaft about which said frame swings and which rises and falls therewith, and a shaft for a saw or rotary cutter carried by said frame, of a guide-link pivoted at its upper part to said frame, a fixed pivot to which the lower part of said link is pivoted, and an adjustable support for said fixed pivot, whereby the adj ustr ment of said pivot is made to adjust the heightof said frame and its shafts and the saw or cutter, substantially as herein described.

The comliiination, with the swinging and rising and falling frame, the driving-shaft rising and falling therewith, the fixed pivot on one side of the lower part of said frame, the guide-link swinging on said fixed pivot, and the upper pivot, (L2, connecting said link with the said frame, of a fixed lateral guide-bearing, D for said frame near said upper pivot, substantially as herein described.

4. The combination, with the swinging and rising and falling frame A, the driving-shaft upon which said frame swings and which rises and falls with it, and the pivoted guidelink D, of the fixed guide-yoke (Z and a support therefor embracing the said link, substantially as and for the purpose herein described.

5. The combination, with the swinging frame which is capable of moving in both directions beyond a vertical position, and the upper part of which is free to rise and fall to permit the guiding of the lower part, of a spring connected with said frame and a fixed support for said spring, upon which the latter is self-reversing, to pull the frame in either direction toward a vertical position, substantially as herein described.

6. The combination, with the swinging frame which is capable of moving in both directions beyond a central vertical line, and the upper part of which is free to rise and fall to permit the guiding of the lower part, of a spring attached to the said frame and a fixed support for said spring on one side of said line, upon which the said spring is selfreversing, to pull the said frame in either direction toward a vertical position, but to exert a greater force upon the said frame in one direction than in the other, substantially as herein described.

EDWARD D. MACKINTOSH.

Witnesses:

FREDK. HAYNES, J os. W. Ron. 

